Drill.



PATENTED MAY 12, 1908.

F. C. PALMER.

DRILL.

APPLICATION FILED JULY 19.1907.

" m-v M-l (K adorn IlNIE ST,

FREDERICK (J. PALMER, OF SPRINGFIELD, MASSACHUSETTS.

- T all whom it may concern.-

Be it known that I, FREDERICK O. PALMER, a citizen of the United States, residing at Springfield, in the county of Hampden and State of Massachusetts, have invented certain new anduseful Improvements in Drills, of which the following is a specification.

My invention relates to drills, and similar tools, and its novelty consists in the construction and adaptation of the'parts, as will be more specifically hereinafter pointed out.

In using drills for the purpose of making holes in masonry into whichbolt anchors and the like are to be inserted, a separable holder, or handle, into which drill points of different size could be inserted, has long been desired,

.but it is diflicult' to make the connections bethe constant and repeatedstrokes of the hammer the drill points worked loose, or stripped the threads. Difiiculty has also been encountered in roviding reliable means, easily operated,'to hold the drills securely, and at the same time removably, in the holder or handle. By my inventionI' have overcome these difficulties. I have made a sim le connection between the holder and t e drill point which is efficient and sure and, while.

around from the position of Fig. 1 Fig. 3 is a similar view with the drill turned half around from the position of Fig. 1; .Fig. 4 is a transverse sectional view on the plane 44 of Fig. 1; Fig. 5 is a similar iview on the plane 5-5 of Fig. 2 ,Fig. 6 is a similar view on the plane of the line 66 of Fig. 3; Fig. 7 is an enlarged side elevation, with the drill removed and the handle broken away, the retaining pin being shown in section; Fig. 8 is an enlarged viewof the spring, the retaining pin and the securing screw removed from'the drill body.

Like reference characters mark the same parts in all of the figures of the drawing.

In the drawings, 1() is the. handle or holder of the drill, the body of the same being cylindrical or polyhedral in shape tapering at 11 toward the head, provided with a longitudi- Sp'ecification of Letters Patent. Application filed July 19, 1907. Serial no. 384,645.

Patented May 12, 1908.

nal central aperture extending inwardly from the head, to receive the shank 12 of the drill 13. The drill 13 comprises the shank 12, provided with a recessed notch 14; a body 15, and an outwardly flared point 16. is suitably serrated at its extremity 1.7, and is hollowed out at 1.8 very nearly to the body 15. It is preferably provided with means for permitting the escape of the air within the hollow portion 18 consisting of a tapering or wedge-shaped notch or slit 19, as shown in Fig. 1, such notch. or slit affording a communication between the outer air and the inner hollow space 18, and the taper or flare of the' diately opposite to the notch is a circular hole or recess 20.

In the holder is formed a circular hole to receive a retaining pin 22 which is provided with a head 23 around which extends an annular groove 24 to receive the forked end 25 of a spring26 which has, near'its opposite end a longitudinal slot 27 through which is passed a securing screw 28 which is threaded into the holder 10.

In the holder opposite the hole 21 is a hole or opening 29 through which a tool may be introduced to slightly bur or upset the inner end of the'retaining pin 22 so that the pin, while permitted tomove freely in and out and to be withdrawn by the application of force, will not drop out should the spring 26 be temporarily removed.

The shank 12 has its inner end made con ical, as at 80, so that it willact as a wedge or incline to permit the shank to -be inserted without withdrawing the retaining pin 22, the latter being pressed outward when the shank is inserted in the body and riding over the shank until it drops into the transverse notch 14.

IN hen the pin, 22, impelled by spring'26, enters the notch 14, the shank 12 will be held against withdrawal from the body under ordinary stress, and to remove the shank, it will only be necessary to turn it to the position shown in Figs. 2 and 5, when it may be freely withdrawn.

Should extraordinary turning strain be put upon the drill, it will turn to this position, and beyond it to the position of Figs. 3 and 6, when the pin will drop into the hole '20, in the same annular zone as notch 14,

The point from which the shank cannot be removed without withdrawing pin 22.

. When eXtra strain is to be guarded against, the shank will be manually laced in the position of Figs. 3 and 6, and i extra security is desired, a pin 32 will be driven into the opening 31, transverse to the pin 22 and to one side of the center of the holder, said pin 22 resting in the notch 14 and reinforcing the pin 22 in thehole 21. In this adjustment, the parts will be rigidly secured, and for all practical purposes, be substantially as strong as though integral. To remove the pin 22, it is only necessary to loosen the screw 28, slide the spring 26 out of the annular groove 24, and apply a reasonable withdrawing force to the head 23.

What I claim as new and desire to secure by Letters Patent is:

1. In combination, a hollow body, a drill having a shank to fit said body and provided With a transverse notch in one side and a circular hole in the opposite side in the same annular zone, and a normally inwardly spring pressed retaining pin seated in a transverse hole in the body in annular register with the notch and hole of the shank when the latter is inserted in the body.

2. In combination, a hollow body, a drill shank fitted therein, a pin having an annular grooved head and seated in a transverse hole in the body and adapted to engage the shank, a spring having a forked end to engage the annular groove of the head and a longitudinal slot near its opposite end, and a screw passing through said slot into the body.

In testimony whereof I affix my signature in'presence of two Witnesses.

FREDERICK O. PALMERQ Witnesses:

HERMAN MEYER, STEPHEN G. NEWTON. 

